IS-84 Colorado Mineral and Energy Industry Activities 2020-2021 – bibliography

Aggregate quarry near Durango, Colorado. Photo credit: Mike O'Keeffe for the CGS.

Every year, the CGS Minerals section prepares a comprehensive survey of the mineral and energy industries across the state. The 2020-2021 report isn’t finished quite yet, but the comprehensive bibliographic list that it is based on is. This list includes state, local and federal government sources, as well as private sector information sites. We thought… Continue reading IS-84 Colorado Mineral and Energy Industry Activities 2020-2021 – bibliography

New GIS data and maps

Detail from one of over 600 Denver Basin geophysical and lithological logs included in the ON-OF-78-08M digitization project. Photo credit: Colorado Geological Survey.

For those of you who are subscribers to the CGS announcement list, we want to direct your attention to a handful of new maps and recently digitized analog data sets that we haven’t otherwise publicized. These include several important online GIS maps and downloadable data packages: ON-008-04D U.S. Forest Service Abandoned Mine Land Inventory Project… Continue reading New GIS data and maps

Colorado’s Uranium Deposits

A uranium-rich zone in a sandstone of the Morrison Formation, Carnation Mine, San Miguel County, Colorado, January 2007. Photo credit: Colorado Geological Survey.

[Ed: this document, written in 2011 by Jim Burnell, Ph.D., P.G. (former Senior Minerals Geologist, Colorado Geological Survey), provides an excellent narrative on the sources of uranium deposits on the Western Slope of Colorado. However, it’s not the whole story—there is fascinating new science research implicating biological/organismic activity underground that affects the movement of uranium… Continue reading Colorado’s Uranium Deposits

Geology of Uranium Deposits in Colorado

Uranium roll front hosted in Dakota Sandstone, Turkey Creek Road road-cut, Dakota Hogback, near Denver, Colorado. Photo credit: James St. John.

Uranium is a widespread and ubiquitous element. It has a crustal abundance of 2.8 parts per million, slightly more than tin. Primary deposits of uranium tend to concentrate in granitic or alkalic volcanic rocks, hydrothermal veins, marine black shales, and early Precambrian age placer deposits. Secondary (or epigenetic) deposits of uranium are formed later than… Continue reading Geology of Uranium Deposits in Colorado